130 Scientific Proceedings, Royal Dublin Society. 



SUMMAEY. 



The deviations in tlie distilla.tion constants of the lower fatty acids, 

 especially in the case of formic and acetic acids, may be explained satisfactorily 

 by taking into account the electrolytic dissociation of the acid. 



By applying a correction for the electrolytic dissociation, the distillation 

 constant is independent of the diluticni. 



The addition of certain salts and acids increases the distillation constant, 

 but the amount of increase appears to depend on the nature of the salt added. 

 The addition of a solution of copper sulphate, containing 1 gram molecule 

 per litre, to a dilute acetic acid solution causes a diminution in the distillation 

 constant. 



The authors have much pleasure in thanking Dr. Y. E. Hackett for the 

 assistance which he has given them during the progress of the work. 



